OSSSC Combined Recruitment Examination cheat sheet

Blood relation: draw a family tree, use + for male and − for female; 'only son of my grandfather' = my father; 'brother of my mother' = maternal uncle (mamu).

Direction sense: fix north upward; right turn = clockwise 90°, left turn = anticlockwise 90°; final displacement uses Pythagoras when path turns at right angles.

Coding-decoding: check letter positions A=1 … Z=26; common shifts are +1, −1, +2, and reversal (A↔Z, B↔Y) mapping to 27 minus position.

Series rule: test differences, then ratios, then squares/cubes (1, 4, 9, 16…) and alternating +n/−n patterns before assuming a single rule.

Odd one out: compare prime/composite status, perfect squares, divisibility by 3 or 5, and alphabet vowel-consonant grouping.

Syllogism: 'All A are B' does not imply 'All B are A'; a conclusion is valid only if true in every possible Venn arrangement of the premises.

Odia GK anchors: Odisha formed as a separate province on 1 April 1936; capital Bhubaneswar; state language Odia; Chilika is Asia's largest brackish-water lagoon.

Odisha geography: Mahanadi is the state's largest river; Deomali in Koraput is the highest peak; Similipal (Mayurbhanj) is a tiger reserve and biosphere reserve.

Scheduling and ranking: in a row of n people, a person at position p from the left is at (n − p + 1) from the right; total = left rank + right rank − 1.

Percentage change: successive changes of a% and b% give a net change of a + b + ab/100 percent; a 20% rise then 20% fall nets −4%.

Profit and loss: SP = CP × (100 + profit%)/100; if two articles are sold at the same price with equal gain% and loss%, the net result is always a loss of (x²/100)%.

Simple interest I = PRT/100; compound interest A = P(1 + R/100)^T, so CI = A − P; for 2 years CI − SI = P(R/100)².

Time-speed-distance: distance = speed × time; to convert km/h to m/s multiply by 5/18; a train crossing a platform covers its own length plus platform length.

Boats and streams: downstream speed = boat + stream, upstream = boat − stream; boat speed = (down + up)/2, stream speed = (down − up)/2.

Ratio and mixture: alligation gives ratio of quantities = (mean − cheaper) : (dearer − mean); repeated dilution leaves P(1 − x/V)^n of the original liquid.

Averages: new average after adding a value = (old total + value)/(n + 1); if every item rises by k, the average rises by k.

Time and work: if A does work in a days and B in b days, together they take ab/(a + b) days; use LCM of days as total work units.

Mensuration: area of circle = πr², circumference = 2πr; volume of cylinder = πr²h; diagonal of a rectangle = √(l² + b²); sum of first n natural numbers = n(n + 1)/2.

Subject-verb agreement: singular subject takes singular verb; 'one of the + plural noun' takes a singular verb ('One of the boys is here'); 'each, every, either, neither' are singular.

Articles: 'a' before consonant sounds, 'an' before vowel sounds (an hour, a university); 'the' with superlatives, unique objects, rivers, ranges, and ordinals.

Tenses: use present perfect for past action with present relevance ('has gone'); past perfect for the earlier of two past actions ('had left before I arrived').

Prepositions: 'since' with a point of time, 'for' with duration; 'good at', 'afraid of', 'married to', 'comprise' takes no 'of'.

Active to passive: object becomes subject, verb becomes be + past participle, agent takes 'by'; only transitive verbs passivise.

Direct to indirect speech: change present to past tense, 'this' to 'that', 'now' to 'then', 'today' to 'that day'; questions use 'if/whether' or the wh-word with statement order.

Common error traps: 'discuss about' and 'return back' are redundant; 'cope up with' should be 'cope with'; use 'fewer' for countable, 'less' for uncountable nouns.

Vocabulary: synonym/antonym items hinge on word class - check whether the stem is a verb, noun, or adjective before choosing; idioms are fixed and not literal ('a bolt from the blue' = sudden shock).

Cloze and comprehension: read the whole passage first, then choose options that fit both grammar and the paragraph's logic; eliminate options that break tense consistency.

Odia script has 11 vowel letters (ସ୍ୱରବର୍ଣ୍ଣ) and about 39 consonant letters (ବ୍ୟଞ୍ଜନବର୍ଣ୍ଣ); conjuncts are formed with the hasanta (୍) mark.

Odia is a classical language status granted in 2014; it is the official language of Odisha and one of the 22 scheduled languages of India.

Sandhi: ଓଡ଼ିଆ uses ସ୍ୱରସନ୍ଧି (vowel), ବ୍ୟଞ୍ଜନସନ୍ଧି (consonant) and ବିସର୍ଗସନ୍ଧି; e.g. ଦେବ + ଆଲୟ = ଦେବାଲୟ.

Samasa (କର୍ମଧାରୟ, ଦ୍ୱନ୍ଦ୍ୱ, ତତ୍ପୁରୁଷ, ବହୁବ୍ରୀହି, ଦ୍ୱିଗୁ, ଅବ୍ୟୟୀଭାବ) classification is a standard grammar question; ଦ୍ୱନ୍ଦ୍ୱ joins items of equal rank.

ସମାନାର୍ଥକ (synonyms) and ବିପରୀତାର୍ଥକ (antonyms) pairs are frequently tested; e.g. ଦିନ ↔ ରାତି, ସତ୍ୟ ↔ ଅସତ୍ୟ.

ଲକ୍ଷଣା ଓ ଅଳଙ୍କାର: ଉପମା (simile) uses ସମାନ ଶବ୍ଦ, ରୂପକ (metaphor) identifies directly without comparison words.

Odia literature: Sarala Das wrote the Odia Mahabharata; Fakir Mohan Senapati is called the father of modern Odia literature and wrote 'Rebati' and 'Chha Mana Atha Guntha'.

Regional knowledge: Odissi is the classical dance of Odisha; Rath Yatra is held at Puri; Konark Sun Temple is a UNESCO World Heritage Site built by Narasimhadeva I.

Odia festivals and geography: Raja, Nuakhai and Bali Jatra are Odisha-specific; the Eastern Ghats run through the state and the Chilika lagoon lies on the eastern coast.